net: bcmgenet: simplify __bcmgenet_tx_reclaim()
1. Use c_index and ring->c_index to determine how many TxCBs/TxBDs are
ready for cleanup
- c_index = the current value of TDMA_CONS_INDEX
- TDMA_CONS_INDEX is HW-incremented and auto-wraparound (0x0-0xFFFF)
- ring->c_index = __bcmgenet_tx_reclaim() cleaned up to this point on
the previous invocation
2. Add bcmgenet_tx_ring->clean_ptr
- index of the next TxCB to be cleaned
- incremented as TxCBs/TxBDs are processed
- value always in range [ring->cb_ptr, ring->end_ptr]
3. Fix incrementing of dev->stats.tx_packets
- should be incremented only when tx_cb_ptr->skb != NULL
These changes simplify __bcmgenet_tx_reclaim(). Furthermore, Tx ring size
can now be any value.
With the old code, Tx ring size had to be a power-of-2:
num_tx_bds = ring->size;
c_index &= (num_tx_bds - 1);
last_c_index &= (num_tx_bds - 1);
Signed-off-by: Petri Gynther <pgynther@google.com>
Reviewed-by: Florian Fainelli <f.fainelli@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
diff --git a/drivers/net/ethernet/broadcom/genet/bcmgenet.h b/drivers/net/ethernet/broadcom/genet/bcmgenet.h
index 016bd12..548b7e9 100644
--- a/drivers/net/ethernet/broadcom/genet/bcmgenet.h
+++ b/drivers/net/ethernet/broadcom/genet/bcmgenet.h
@@ -525,6 +525,7 @@
unsigned int queue; /* queue index */
struct enet_cb *cbs; /* tx ring buffer control block*/
unsigned int size; /* size of each tx ring */
+ unsigned int clean_ptr; /* Tx ring clean pointer */
unsigned int c_index; /* last consumer index of each ring*/
unsigned int free_bds; /* # of free bds for each ring */
unsigned int write_ptr; /* Tx ring write pointer SW copy */